In-game, they're more powerful (from the increased velocity, just as in reality) and cause your weapon to wear more quickly, which is the 'Gun CND'. Many firearms' warranty information specifically forbids use of +P ammunition, with warnings that the warranty is void the moment such a round is fired. +P rounds are loaded to produce more pressure than the 'standard allowable' levels, with warnings to use them only in specific weapons designed (or at least approved) for very high-powered high-pressure rounds. 45-70 Government actually sees this effect, max pressure being set to account for US Civil War era Trapdoor Springfield rifles still in circulation) This pressure can be quite low for some cartridges, to account for there being antique arms in that chambering which may not be as strong as a new weapon in the same caliber. +P stands for '+ Pressure.' Real-world, every cartridge has a maximum allowable firing chamber pressure for safety purposes. How many other strange ammo type names are there and what are their stats like? Does this mean it does more damage to my gun than an normal 9mm ammo, or less? Or does it mean something else completely?

What is the +P supposed to mean? There also seems to be some indication it does something to the condition of the gun (Gun CND x 1.20). However, there General Store in Goodsprings is selling 9mm +P ammo. Understanding Armour Piercing and Hollow Point ammo is easy enough.

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